Liquid fuel nuclear fission reactor

ABSTRACT

Disclosed embodiments include nuclear fission reactors, nuclear fission fuel pins, methods of operating a nuclear fission reactor, methods of fueling a nuclear fission reactor, and methods of fabricating a nuclear fission fuel pin.

BACKGROUND

This patent application relates to nuclear fission reactors.

SUMMARY

Disclosed embodiments include nuclear fission reactors, nuclear fissionfuel pins, methods of operating a nuclear fission reactor, methods offueling a nuclear fission reactor, and methods of fabricating a nuclearfission fuel pin.

The foregoing is a summary and thus may contain simplifications,generalizations, inclusions, and/or omissions of detail; consequently,those skilled in the art will appreciate that the summary isillustrative only and is NOT intended to be in any way limiting. Otheraspects, features, and advantages of the devices and/or processes and/orother subject matter described herein will become apparent in theteachings set forth herein.

BRIEF DESCRIPTION OF THE FIGURES

FIGS. 1A-1C are top plan views in partial schematic form of illustrativenuclear fission reactors.

FIGS. 1D-1F are side plan views in partial schematic form ofillustrative nuclear fission reactors.

FIG. 1G is a side plan view in partial schematic form of an illustrativenuclear fission fuel pin.

FIG. 1H is a top plan view in partial schematic form of an illustrativenuclear fission reactor.

FIG. 1I it is a side plan view in partial schematic form of anillustrative nuclear fission reactor.

FIG. 1J is a perspective view in partial cutaway of an illustrativenuclear fission reactor.

FIG. 2A is a top plan view in partial schematic form of an illustrativenuclear fission reactor.

FIG. 2B is a side plan view in partial schematic form of an illustrativenuclear fission reactor.

FIG. 2C is a top plan view in partial schematic form of an illustrativenuclear fission reactor.

FIG. 2D is a side plan view in partial schematic form of an illustrativenuclear fission reactor.

FIG. 2E is a perspective view in partial cutaway of an illustrativenuclear fission reactor.

FIG. 3A is a side plan view in partial schematic form of an illustrativenuclear fission reactor.

FIGS. 4A-4C are side plan views in partial schematic form ofillustrative nuclear fission fuel pins.

FIG. 5A is a flowchart of an illustrative method of operating a nuclearfission reactor.

FIGS. 5B-5D are flowcharts of illustrative details of the method of FIG.5A.

FIG. 6A is a flowchart of an illustrative method of operating a nuclearfission reactor.

FIGS. 6B-6E are flowcharts of illustrative details of the method of FIG.6A.

FIG. 7A is a flowchart of an illustrative method of operating a nuclearfission reactor.

FIGS. 7B-7G are flowcharts of illustrative details of the method of FIG.7A.

FIG. 8A is a flowchart of an illustrative method of fueling a nuclearfission reactor.

FIGS. 8B-8H are flowcharts of illustrative details of the method of FIG.8A.

FIG. 9A is a flowchart of an illustrative method of fabricating anuclear fission fuel pin.

FIGS. 9B-9J are flowcharts of illustrative details of the method of FIG.9A.

FIG. 10A is a flowchart of an illustrative method of fabricating anuclear fission fuel pin.

FIGS. 10B-10I are flowcharts of illustrative details of the method ofFIG. 10A.

DETAILED DESCRIPTION

In the following detailed description, reference is made to theaccompanying drawings, which form a part hereof. In the drawings,similar symbols typically identify similar components, unless contextdictates otherwise. The illustrative embodiments described in thedetailed description, drawings, and claims are not meant to be limiting.Other embodiments may be utilized, and other changes may be made,without departing from the spirit or scope of the subject matterpresented here.

The present application uses formal outline headings for clarity ofpresentation. However, it is to be understood that the outline headingsare for presentation purposes, and that different types of subjectmatter may be discussed throughout the application (e.g.,devices/structures may be described under processes/operations headingsand/or processes/operations may be discussed under structures/processesheadings; and/or descriptions of single topics may span two or moretopic headings). Hence, the use of the formal outline headings is notintended to be in any way limiting.

Illustrative Nuclear Fission Reactors

Given by way of overview and referring to FIG. 1A, in a non-limitingembodiment an illustrative nuclear fission reactor 10 includes a reactorvessel 12. A solution 14 of fissile nuclear fission fuel materialdissolved in neutronically translucent liquid carrier material isreceived in the reactor vessel 12. Undissolved fertile nuclear fissionfuel material 16 is disposed in contact with the solution 14. Thefertile nuclear fission fuel material 16 is transmutable into thefissile nuclear fission fuel material.

Still by way of overview, in operation a portion of the undissolvedfertile nuclear fission fuel material 16 is transmuted into the fissilenuclear fission fuel material. The transmuted fissile nuclear fissionfuel material is diffused to the solution 14.

Thus, in some embodiments diffusion of transmuted fissile nuclearfission fuel material to the solution 14 could help replenish a portionof the fissile nuclear fission fuel material that is consumed duringfissioning of the fissile nuclear fission fuel material.

Non-limiting, illustrative details will be set forth below by way ofexample and not of limitation.

Still referring to FIG. 1A, solubility of the fissile nuclear fissionfuel material in the neutronically translucent liquid carrier materialis greater than solubility of the fertile nuclear fission fuel material16 in the neutronically translucent liquid carrier material. In someembodiments and as mentioned above, the fissile nuclear fission fuelmaterial is solvable in the neutronically translucent liquid carriermaterial, thereby making the solution 14. In some embodiments, thefertile nuclear fission fuel material 16 is substantially insoluble inthe neutronically translucent liquid carrier material.

The liquid carrier material, the fissile nuclear fission fuel material,and the fertile nuclear fission fuel material 16 may be selected amongas desired according to the above solubility and neutronic translucencyrelationships.

For example, in various embodiments the neutronically translucent liquidcarrier material may include liquid materials such as Mg, Ag, Ca, Ni,and the like. In some embodiments the fissile nuclear fission fuelmaterial may include ²³⁹Pu. Also, in some embodiments the fertilenuclear fission fuel material 16 may include ²³⁸U.

An example will be explained by way of illustration and not oflimitation. In one illustrative embodiment, the liquid carrier materialmay include liquid Mg, the fissile nuclear fission fuel material mayinclude ²³⁹Pu, and the fertile nuclear fission fuel material 16 mayinclude ²³⁸U. In such an illustrative case, Mg has a melting pointaround 650° C. The liquid Mg carrier material is a solvent for the ²³⁹Pufissile nuclear fission fuel material, and the plutonium lowers themelting point of the magnesium. Given by way of non-limiting example, ataround 5 atom percent Pu, a eutectic composition is formed with amelting temperature of around 600° C. The liquid Mg carrier material isnot a solvent for the ²³⁸U fertile nuclear fission fuel material 16 (andis substantially immiscible in solid and liquid form). Also, Mg has aneutron absorption cross section in the fast spectrum on the order ofaround 1 mb. Such a low neutron cross section in the fast spectrum thusmakes the liquid Mg carrier material neutronically translucent to the²³⁹Pu fissile nuclear fission fuel material.

It will be appreciated that mass transfer diffusion coefficients affectdiffusion of the transmuted fissile nuclear fission fuel material. Forthe non-limiting combination of materials discussed above, the masstransfer diffusion coefficient for Pu through liquid Mg is approximately1 E-05 cm²/s. As will be discussed further below, the transmuted fissilenuclear fission fuel material first diffuses through the fertile nuclearfission fuel material 16 to get to the solution 14. With that in mind,the mass transfer diffusion coefficient for Pu through U isapproximately 1 E-12 cm²/s.

As mentioned above, the undissolved fertile nuclear fission fuelmaterial 16 is disposed in contact with the solution 14. In someembodiments, the fertile nuclear fission fuel material 16 may be indirect physical contact with the neutronically translucent liquidcarrier material. Moreover, in some embodiments the fertile nuclearfission fuel material 16 may be suspended in the neutronicallytranslucent liquid carrier material.

To that end, in some embodiments the fertile nuclear fission fuelmaterial 16 may be provided in solid form. In various embodiments, thefertile nuclear fission fuel material may be provided in various formssuch as granular form, wire form, plate form, foam form, and the like.

Regardless of form in which the fertile nuclear fission fuel material isprovided and as mentioned above, the transmuted fissile nuclear fissionfuel material first diffuses through the fertile nuclear fission fuelmaterial 16 to get to the solution 14. It will be appreciated that thelarger the specific surface area provided by the form of the fertilenuclear fission fuel material, the greater the rate of diffusion oftransmuted fissile nuclear fission fuel material through the fertilenuclear fission fuel material to the liquid carrier material. It willalso be appreciated that, when the fertile nuclear fission fuel materialis provided in granular form, a small particle size can help introduce alarge concentration gradient (of transmuted fissile nuclear fission fuelmaterial) without large differences in concentration (between transmutedfissile nuclear fission fuel material distributed in the fertile nuclearfission fuel material and fissile nuclear fission fuel materialdissolved in the neutronically translucent liquid carrier material).Thus, a concentration of the fissile nuclear fission fuel material inthe fertile nuclear fission fuel material 16 is established that isgreater than a concentration of the fissile nuclear fission fuelmaterial in the neutronically translucent liquid carrier material. It isthis concentration gradient that causes the transmuted fissile nuclearfission fuel material to diffuse through the fertile nuclear fissionfuel material 16 to the solution 14.

Still referring to FIG. 1A, the solution 14 and the fertile nuclearfission fuel material 16 may be distributed in the reactor vessel 12 inany manner as desired. To that end, no limitation is implied, and is notto be inferred, from the illustration shown in FIG. 1A.

Referring now to FIG. 1B, in some embodiments the solution 14 and thefertile nuclear fission fuel material 16 may be distributedhomogeneously in the reactor vessel 12. For example, the fertile nuclearfission fuel material 16 may be provided in any format that may lenditself to homogeneous distribution within the solution 14, such aswithout limitation any one or more format like pellets, rods, particlesuspension, foam, and the like.

Given by way of nonlimiting example of a homogeneous distribution, fordepleted U in the 60 v/o range, 8-9 v/o of Pu in Mg is entailed in orderto attain a potentially critical configuration (that is, k_(∞), >1). Toomuch depleted U by volume results in k_(∞)<1, which is not useable as afuel (that is, it does not become self-sustaining). At about 9 v/o Pu inMg (around 50 w/o Pu), liquid Pu comes out of solution from the Mg andforms a two liquid system, so this is another constraint on the level ofPu from the high end.

The effect of the depleted U on k_(∞) can be reduced in any one or moreof several ways, such as by: (i) suspending the U at a reducedconcentration in the Pu—Mg solution, thereby resulting in a higherk_(∞); or (ii) diluting the U with a solid, insoluble, neutronicallytranslucent material such as MgO; or (iii) providing the U in a foamform with much higher porosity and hence lower concentration, therebyresulting in a higher k_(∞).

In any of these cases, if the U content is reduced to below about 50v/o, then a lower Pu concentration, such as on the order of around 3-5v/o, can result in k_(∞)>1.

In some other embodiments and referring to FIGS. 1C and 1D, the solution14 and the fertile nuclear fission fuel material 16 may be distributedheterogeneously in the reactor vessel 12. The heterogeneous distributionmay be any heterogeneous distribution as desired and is not intended tobe limited to heterogeneous distributions shown in the drawings.

Given by way of non-limiting example and as shown in FIG. 1C, in someembodiments a portion 18 of the solution 14 may be received in a fissionregion 20 of the reactor vessel 12. The fertile nuclear fission fuelmaterial 16 and a portion 22 of the solution 14 may be received in afertile blanket region 24 of the reactor vessel 12. In such embodiments,the fertile blanket region 24 is in hydraulic communication with thefission region 20 (because the liquid carrier material occupies thefission region 20 and the fertile blanket region 24) and neutroniccommunication with the fission region 20 (because the solution 14 of thefissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material occupies the fission region 20 andthe fertile blanket region 24).

In other embodiments and referring now to FIG. 1E, nuclear fission fuelpins 26 may be received in the reactor vessel 12. Each nuclear fissionfuel pin 26 has an axial end 28 and an axial end 30.

Referring additionally to FIG. 1F, in some embodiments a portion 32 ofat least one of the nuclear fission fuel pins 26 may be disposed in thefission region 20 and at least a portion 34 of the at least one nuclearfission fuel pin 26 may be disposed in a fertile blanket region 24.

Referring additionally to FIG. 1G, in some embodiments the solution 14is distributed throughout each of the plurality of nuclear fission fuelpins 26 and the fertile nuclear fission fuel material 16 may be receivedin fertile blanket zones 36 and 38 disposed toward the axial ends 28 and30. Thus, it will be appreciated that in some embodiments a fertileblanket region 24 (FIG. 1F) could be located toward the axial ends 28 ofthe nuclear fission fuel pins 26 and another fertile blanket region 24(FIG. 1F) could be located toward the axial ends 30 of the nuclearfission fuel pins 26.

Referring now to FIGS. 1H and 1J, in some embodiments fertile blanketmodules 40 may be disposed in the fertile blanket region 20. In suchembodiments the fertile nuclear fission fuel material 16 is received inthe fertile blanket modules 40.

Referring now to FIGS. 1I and 1J, in some embodiments at least one heatexchanger element 42 may be disposed in thermal communication with thesolution 14. FIG. 1I represents a general depiction of an embodiment inpartial schematic form while FIG. 1J represents a more detailed view ofan embodiment that includes the fertile blanket modules 40. In somecases, the heat exchanger element 42 may be immersed in the solution 14.Also, in some cases an annulus 44 may be disposed in the reactor vessel12 adjacent the heat exchanger element 42 such that natural circulationof the solution may be established through the heat exchanger element 42and around the annulus 44.

To that end, the reactor vessel 12 is filled with the solution 14 up toa level 45 that is above the heat exchanger element 42 and the annulus44. In such an arrangement, heat from fission in the fission region 20causes the fissile solution 14 to rise, as indicated by arrow 46. Therising solution 14 flows around the annulus 44 into the heat exchangerelement 42, as indicated by arrows 47. The heat exchanger element 42cools the solution 14 that flows therethrough. The solution 14 that hasbeen cooled by the heat exchanger element 42 moves downwardly asindicated by arrows 48. The downwardly-flowing solution 14 flows aroundthe annulus 44 and into the fission region 20, as indicated by arrows49, thereby establishing a natural circulation loop.

It will be appreciated that reactivity may be controlled in any manneras desired. For example, given by way of illustration and not oflimitation, reactivity may be controlled by way of any one or moreillustrative reactivity control methodologies, such as withoutlimitation: dissolving neutron absorbing poisons in the liquid carriermaterial; inserting and extracting control rods (not shown) of neutronabsorbing material into and out of the solution 14; redistributing thefertile nuclear fission fuel material 16 and the fissile nuclear fissionfuel material as desired; adding neutronically translucent liquidcarrier material to reduce concentration of fissile nuclear fission fuelmaterial in the neutronically translucent liquid carrier material;inserting neutronically translucent material to displace the solution 14(that contains fissile nuclear fission fuel material); and/or the like.

Reactivity may be controlled in similar manners in all embodimentsdisclosed herein. As such, for the sake of brevity, details ofreactivity control need not be repeated in all embodiments for anunderstanding of the disclosed embodiments.

Now that an overview of embodiments and aspects has been set forth,additional embodiments, aspects, and illustrative details will bedescribed. In the interest of brevity, details for components that arecommon to previously-described embodiments need not and will not berepeated, and the same reference numbers will be re-used.

Referring now to FIGS. 2A and 2B, a nuclear fission reactor 210 includesa reactor vessel 12 having a solution 14 of fissile nuclear fissionmaterial dissolved in neutronically translucent liquid carrier material.The reactor vessel 12 defines a fission region 20 toward a centralizedregion 221 of the reactor vessel 12 and a fertile blanket region 24toward a peripheral region 225 of the reactor vessel 12. Undissolvedfertile nuclear fission fuel material 16 is disposed in the fertileblanket region 24 in contact with the solution. The fertile nuclearfission fuel material 16 is transmutable into the fissile nuclearfission material.

In some embodiments the reactor vessel 12 may be cylindrical. In suchcases and as shown in FIG. 2A, the peripheral region 225 may include aradially peripheral region. However, the reactor vessel 12 need not becylindrical, and may have any shape as desired. Regardless of shape ofthe reactor vessel 12 and as shown in FIG. 2B, in some embodiments theperipheral region 225 may include an axially peripheral region. As alsoshown in FIG. 2B, it will be appreciated that fertile blanket regions 24may be established at both axially peripheral regions 225. However, itwill also be appreciated that fertile blanket regions 24 need not beestablished at both axially peripheral regions 225. To that end and insome embodiments, a fertile blanket region 24 may be established ateither one but not both of the axially peripheral regions 225.

Some aspects that previously have been explained in detail will bementioned briefly below. As discussed above, solubility of the fissilenuclear fission fuel material in the neutronically translucent liquidcarrier material is greater than solubility of the fertile nuclearfission fuel material 16 in the neutronically translucent liquid carriermaterial. In some embodiments and as mentioned above, the fissilenuclear fission fuel material is solvable in the neutronicallytranslucent liquid carrier material, thereby making the solution 14. Insome embodiments, the fertile nuclear fission fuel material 16 issubstantially insoluble in the neutronically translucent liquid carriermaterial.

In various embodiments, the neutronically translucent liquid carriermaterial may include liquid materials such as Mg, Ag, Ca, Ni, and thelike. In some embodiments the fissile nuclear fission fuel material mayinclude ²³⁹Pu. Also, in some embodiments the fertile nuclear fissionfuel material 16 may include ²³⁸U.

As mentioned above, the undissolved fertile nuclear fission fuelmaterial 16 is disposed in contact with the solution 14. In someembodiments, the fertile nuclear fission fuel material 16 may be indirect physical contact with the neutronically translucent liquidcarrier material. Moreover, in some embodiments the fertile nuclearfission fuel material 16 may be suspended in the neutronicallytranslucent liquid carrier material.

In some embodiments the fertile nuclear fission fuel material 16 may beprovided in solid form. In various embodiments, the fertile nuclearfission fuel material may be provided various forms such as granularform, wire form, plate form, foam form, and the like.

Referring now to FIGS. 2C and 2E, in some embodiments fertile blanketmodules 40 may be disposed in the fertile blanket region 20 toward theperipheral region 225. In such embodiments the fertile nuclear fissionfuel material 16 is received in the fertile blanket modules 40.

Referring now to FIGS. 2D and 2E, in some embodiments at least one heatexchanger element 42 may be disposed in thermal communication with thesolution 14. FIG. 2D represents a general depiction of an embodiment inpartial schematic form while FIG. 2E represents a more detailed view ofan embodiment that includes the fertile blanket modules 40 disposedtoward the peripheral region 225. In some cases, the heat exchangerelement 42 may be immersed in the solution 14. Also, in some cases anannulus 44 may be disposed in the reactor vessel 12 adjacent the heatexchanger element 42 such that natural circulation of the solution maybe established through the heat exchanger element 42 and around theannulus 44. Details are similar to those described above with referenceto FIGS. 1H-1J and need not be repeated.

Referring now to FIG. 3A, in another illustrative embodiment a nuclearfission reactor 300 includes a reactor vessel 12 and nuclear fissionfuel pins 26 received in the reactor vessel 12. Each nuclear fissionfuel pin has an axial end 28 and an axial end 30. A solution 14 offissile nuclear fission material is dissolved in neutronicallytranslucent liquid carrier material, and the solution 14 is distributedthroughout each nuclear fission fuel pin 26. A centralized axial region321 of the nuclear fission fuel pins 26 defines a fission region 20 ofthe reactor vessel 12. Undissolved fertile nuclear fission fuel material16 is disposed in contact with the solution in fertile blanket zones 36and 38 disposed toward the axial ends 28 and 30, respectively, of eachnuclear fission fuel pin 26. The fertile nuclear fission fuel material16 is transmutable into the fissile nuclear fission material. Thefertile blanket zones 36 and 38 of the nuclear fission fuel pins 26define the fertile blanket regions 24.

An illustrative nuclear fission fuel pin 26 has been discussed abovewith reference to FIG. 1G, and its details need not be repeated. Someaspects that previously have been explained in detail will be mentionedbriefly below.

As discussed above, solubility of the fissile nuclear fission fuelmaterial in the neutronically translucent liquid carrier material isgreater than solubility of the fertile nuclear fission fuel material 16in the neutronically translucent liquid carrier material. In someembodiments and as mentioned above, the fissile nuclear fission fuelmaterial is solvable in the neutronically translucent liquid carriermaterial, thereby making the solution 14. In some embodiments, thefertile nuclear fission fuel material 16 is substantially insoluble inthe neutronically translucent liquid carrier material.

In various embodiments, the neutronically translucent liquid carriermaterial may include liquid materials such as Mg, Ag, Ca, Ni, and thelike. In some embodiments the fissile nuclear fission fuel material mayinclude ²³⁹Pu. Also, in some embodiments the fertile nuclear fissionfuel material 16 may include ²³⁸U.

As mentioned above, the undissolved fertile nuclear fission fuelmaterial 16 is disposed in contact with the solution 14. In someembodiments, the fertile nuclear fission fuel material 16 may be indirect physical contact with the neutronically translucent liquidcarrier material. Moreover, in some embodiments the fertile nuclearfission fuel material 16 may be suspended in the neutronicallytranslucent liquid carrier material.

In some embodiments the fertile nuclear fission fuel material 16 may beprovided in solid form. In various embodiments, the fertile nuclearfission fuel material may be provided various forms such as granularform, wire form, plate form, foam form, and the like.

Illustrative Nuclear Fission Fuel Pins

Referring now to FIG. 4A, in another illustrative embodiment a nuclearfission fuel pin 426 includes cladding 450 that defines an elongatedenclosure 452. A solution 14 of fissile nuclear fission fuel material isdissolved in neutronically translucent liquid carrier material. Thesolution 14 is distributed throughout the elongated enclosure 452.Undissolved fertile nuclear fission fuel material 16 is disposed incontact with the solution 14 in the elongated enclosure 452. The fertilenuclear fission fuel material 16 is transmutable into the fissilenuclear fission fuel material.

In some embodiments the elongated enclosure 452 has axial ends 28 and 30and a centralized axial region 29 between the axial ends 28 and 30.

Still referring to FIG. 4A, the solution 14 and the fertile nuclearfission fuel material 16 may be distributed in the elongated enclosure452 in any manner as desired. To that end, no limitation is implied, andis not to be inferred, from the illustration shown in FIG. 4A. In someembodiments the solution 14 and the fertile nuclear fission fuelmaterial 16 may be distributed homogeneously in the elongated enclosure452.

Referring now to FIG. 4B, in some other embodiments the solution 14 andthe fertile nuclear fission fuel material 16 may be distributedheterogeneously in the elongated enclosure 452. The heterogeneousdistribution may be any heterogeneous distribution as desired and is notintended to be limited to heterogeneous distributions shown in thedrawings.

Still referring to FIG. 4B, in some embodiments the centralized axialregion 29 defines a fission region 20 of the nuclear fission fuel pin426.

In some embodiments the fertile nuclear fission fuel material 16 may bedisposed toward the axial ends 28 and 30. In such cases, the axial ends28 and 30 may define fertile blanket zones 36 and 38, respectively, ofthe nuclear fission fuel pin 426.

Some aspects that previously have been explained in detail will bementioned briefly below.

Referring now to FIGS. 4A and 4B and as discussed above, solubility ofthe fissile nuclear fission fuel material in the neutronicallytranslucent liquid carrier material is greater than solubility of thefertile nuclear fission fuel material 16 in the neutronicallytranslucent liquid carrier material. In some embodiments and asmentioned above, the fissile nuclear fission fuel material is solvablein the neutronically translucent liquid carrier material, thereby makingthe solution 14. In some embodiments, the fertile nuclear fission fuelmaterial 16 is substantially insoluble in the neutronically translucentliquid carrier material.

In various embodiments, the neutronically translucent liquid carriermaterial may include liquid materials such as Mg, Ag, Ca, Ni, and thelike. In some embodiments the fissile nuclear fission fuel material mayinclude ²³⁹Pu. Also, in some embodiments the fertile nuclear fissionfuel material 16 may include ²³⁸U.

As mentioned above, the undissolved fertile nuclear fission fuelmaterial 16 is disposed in contact with the solution 14. In someembodiments, the fertile nuclear fission fuel material 16 may be indirect physical contact with the neutronically translucent liquidcarrier material. Moreover, in some embodiments the fertile nuclearfission fuel material 16 may be suspended in the neutronicallytranslucent liquid carrier material.

In some embodiments the fertile nuclear fission fuel material 16 may beprovided in solid form. In various embodiments, the fertile nuclearfission fuel material may be provided various forms such as granularform, wire form, plate form, foam form, and the like.

Referring now to FIG. 4C, in some embodiments the fertile nuclearfission fuel material 16 may disposed in contact with a wall of theelongated enclosure 452. Given by way of non-limiting example, thefertile nuclear fission fuel material 16 may be disposed in contact withan inner surface 456 of the wall 454.

Now that various embodiments including nuclear fission reactors andnuclear fission fuel pins have been discussed, other embodimentsincluding various methods will be discussed below. Further illustrativedetails regarding neutronics and mass transfer will be set forth by wayof non-limiting examples.

Illustrative Methods

Following are a series of flowcharts depicting implementations. For easeof understanding, the flowcharts are organized such that the initialflowcharts present implementations via an example implementation andthereafter the following flowcharts present alternate implementationsand/or expansions of the initial flowchart as either sub-componentoperations or additional component operations building on one or moreearlier-presented flowcharts. Those having skill in the art willappreciate that the style of presentation utilized herein (e.g.,beginning with a presentation of a flowchart presenting an exampleimplementation and thereafter providing additions to and/or furtherdetails in subsequent flowcharts) generally allows for a rapid and easyunderstanding of the various process implementations. In addition, thoseskilled in the art will further appreciate that the style ofpresentation used herein also lends itself well to modular and/orobject-oriented program design paradigms.

Illustrative details regarding the fissile nuclear fission fuelmaterial, the neutronically translucent carrier material, the solutionof the fissile nuclear fission fuel material dissolved in theneutronically translucent carrier material, and the fertile nuclearfission fuel material have been discussed above and need not be repeatedin the context of the following illustrative, non-limiting methods.

Referring now to FIG. 5A, in an embodiment an illustrative method 500 isprovided for operating a nuclear fission reactor. The method 500 startsat a block 502. At a block 504 a portion of undissolved fertile nuclearfission fuel material is transmuted into fissile nuclear fission fuelmaterial, with the undissolved fertile nuclear fission fuel materialbeing disposed in contact with a solution of the fissile nuclear fissionfuel material dissolved in neutronically translucent liquid carriermaterial. Given by way of example and not of limitation, when ²³⁸U isexposed to a neutron flux, the ²³⁸U will be transmuted to ²³⁹Pu. Moreparticularly, when an atom of ²³⁸U is exposed to a neutron flux, itsnucleus will capture a neutron, thereby changing it to ²³⁹U. The ²³⁹Uthen rapidly undergoes two beta decays. After the ²³⁸U absorbs a neutronto become ²³⁹U it then emits an electron and an anti-neutrino ( ν ^(ε))by β⁻ decay to become ²³⁹Np and then emits another electron andanti-neutrino by a second β⁻ decay to become ²³⁹Pu. At a block 506 thetransmuted fissile nuclear fission fuel material is diffused to thesolution. The method 500 stops at a block 508.

Referring additionally to FIG. 5B, in some embodiments at a block 510intermediate transmuted material may be diffused to the solution. Givenby way of non-limiting examples, as discussed above the intermediatetransmuted material may include without limitation ²³⁹U and ²³⁹Np.

Referring additionally to FIG. 5C, in some embodiments at a block 512 aportion of the fissile nuclear fission fuel material fissions. In suchcases, fissioning of the fissile nuclear fission fuel material canprovide the neutron flux to which the fertile nuclear fission fuelmaterial is exposed, thereby causing transmuting of a portion ofundissolved fertile nuclear fission fuel material at the block 504 (FIG.5A).

Referring additionally to FIG. 5D, in some embodiments diffusing thetransmuted fissile nuclear fission fuel material to the solution at theblock 506 may include diffusing the transmuted fissile nuclear fissionfuel material through the undissolved fertile nuclear fission fuelmaterial at a block 514. For example and as discussed above, regardlessof form in which the fertile nuclear fission fuel material is provided,the larger the specific surface area provided by the form of the fertilenuclear fission fuel material, the greater the rate of diffusion oftransmuted fissile nuclear fission fuel material through the fertilenuclear fission fuel material to the liquid carrier material. It willalso be appreciated that, when the fertile nuclear fission fuel materialis provided in granular form, a small particle size can help introduce alarge concentration gradient (of dissolved fissile nuclear fission fuelmaterial) without large differences in concentration (between transmutedfissile nuclear fission fuel material dissolved in the fertile nuclearfission fuel material and fissile nuclear fission fuel materialdissolved in the neutronically translucent liquid carrier material).Thus, a concentration of the fissile nuclear fission fuel material inthe fertile nuclear fission fuel material is established that is greaterthan a concentration of the fissile nuclear fission fuel material in theneutronically translucent liquid carrier material. It is thisconcentration gradient that causes the transmuted fissile nuclearfission fuel material to diffuse through the fertile nuclear fissionfuel material to the solution.

Referring now to FIG. 6A, in another illustrative embodiment a method600 is provided for operating a nuclear fission reactor. The method 600starts at a block 602. At a block 604 a first concentration isestablished of fissile nuclear fission fuel material in a solution ofthe fissile nuclear fission fuel material dissolved in neutronicallytranslucent liquid carrier material. At a block 606 a secondconcentration is established of the fissile nuclear fission fuelmaterial in undissolved fertile nuclear fission fuel material disposedin contact with the solution, with the second concentration beinggreater than the first concentration. At a block 608 fissile nuclearfission fuel material is diffused through the undissolved fertilenuclear fission fuel material toward the solution. The method 600 stopsat a block 610.

Referring additionally to FIG. 6B, in some embodiments establishing afirst concentration of fissile nuclear fission fuel material in asolution of the fissile nuclear fission fuel material dissolved inneutronically translucent liquid carrier material at the block 604 mayinclude consuming a portion of the fissile nuclear fission fuel materialin the solution of the fissile nuclear fission fuel material dissolvedin neutronically translucent liquid carrier material at a block 612.Referring additionally to FIG. 6C and given by way of non-limitingexample, consuming a portion of the fissile nuclear fission fuelmaterial in the solution of the fissile nuclear fission fuel materialdissolved in neutronically translucent liquid carrier material at theblock 612 may include fissioning a portion of the fissile nuclearfission fuel material in the solution of the fissile nuclear fissionfuel material dissolved in neutronically translucent liquid carriermaterial at a block 614.

Referring additionally to FIG. 6D, in some embodiments establishing asecond concentration of the fissile nuclear fission fuel material inundissolved fertile nuclear fission fuel material disposed in thesolution, the second concentration being greater than the firstconcentration, at the block 606 may include transmuting a portion of thefertile nuclear fission fuel material into the fissile nuclear fissionfuel material at a block 616. Given by way of example and not oflimitation, in some embodiments as discussed above when ²³⁸U is exposedto a neutron flux, the ²³⁸U will be transmuted to ²³⁹Pu. Moreparticularly, when an atom of ²³⁸U is exposed to a neutron flux, itsnucleus will capture a neutron, thereby changing it to ²³⁹U. The ²³⁹Uthen rapidly undergoes two beta decays. After the ²³⁸U absorbs a neutronto become ²³⁹U it then emits an electron and an anti-neutrino ( ν _(ε))by β⁻ decay to become 239Np and then emits another electron andanti-neutrino by a second β⁻ decay to become ²³⁹Pu.

Referring additionally to FIG. 6E, in some embodiments at a block 618intermediate transmuted material may be diffused to the solution. Givenby way of non-limiting examples, as discussed above the intermediatetransmuted material may include without limitation ²³⁹U and ²³⁹Np.

Referring now to FIG. 7A, in another embodiment a method 700 is providedfor operating a nuclear fission reactor. The method 700 starts at ablock 702. At a block 704, in a fission region of a reactor core of anuclear fission reactor, a portion of fissile nuclear fission fuelmaterial, in a solution of the fissile nuclear fission fuel materialdissolved in neutronically translucent liquid carrier material, isfissioned.

At a block 706, in a fertile blanket region of the reactor core,material a portion of undissolved fertile nuclear fission fuel materialdisposed in contact with the solution is transmuted into the fissilenuclear fission fuel. Given by way of example and not of limitation, insome embodiments as discussed above when ²³⁸U is exposed to a neutronflux (such as may be caused by leakage from the fission region ofneutrons from fissioning of the fissile nuclear fission fuel material atthe block 704), the ²³⁸U will be transmuted to ²³⁹Pu. More particularlyand as discussed above, when an atom of ²³⁸U is exposed to a neutronflux, its nucleus will capture a neutron, thereby changing it to ²³⁹U.The ²³⁹U then rapidly undergoes two beta decays. After the ²³⁸U absorbsa neutron to become ²³⁹U it then emits an electron and an anti-neutrino( ν _(ε)) by β⁻ decay to become ²³⁹Np and then emits another electronand anti-neutrino by a second β⁻ decay to become ²³⁹Pu.

At a block 708 the transmuted fissile nuclear fission fuel is diffused.The method 700 stops at a block 710.

Referring additionally to FIG. 7B, diffusing the transmuted fissilenuclear fission fuel material at the block 708 may include diffusing thetransmuted fissile nuclear fission fuel material through the fertilenuclear fission fuel material at a block 712. For example and referringadditionally to FIG. 7C, diffusing the transmuted fissile nuclearfission fuel material through the fertile nuclear fission fuel materialat the block 714 may include diffusing the transmuted fissile nuclearfission fuel material through the fertile nuclear fission fuel materialto the solution at a block 714.

Referring now to FIGS. 7A and 7D, in some embodiments, in a fissionregion of a reactor core of a nuclear fission reactor, fissioning aportion of fissile nuclear fission fuel material in a solution of thefissile nuclear fission fuel material dissolved in neutronicallytranslucent liquid carrier material at the block 704 may include, in afission region of a reactor core of a nuclear fission reactor, consuminga portion of fissile nuclear fission fuel material in the solution ofthe fissile nuclear fission fuel material dissolved in neutronicallytranslucent liquid carrier material at a block 716.

Referring additionally to FIG. 7E, it will be appreciated that, in afission region of a reactor core of a nuclear fission reactor, consuminga portion of fissile nuclear fission fuel material in the solution ofthe fissile nuclear fission fuel material dissolved in neutronicallytranslucent liquid carrier material at the block 716 may includeestablishing in the fissile region a first concentration of the fissilenuclear fission fuel material in the solution at a block 718.

Referring additionally to FIG. 7F, it will also be appreciated that, ina fertile blanket region of the reactor core, transmuting into thefissile nuclear fission fuel material a portion of undissolved fertilenuclear fission fuel material disposed in the solution at the block 706may include establishing, in the fertile blanket region, a secondconcentration of the fissile nuclear fission fuel material in thefertile nuclear fission fuel material, the second concentration beinggreater than the first concentration at a block 720.

Referring additionally to FIG. 7G, in some embodiments at a block 722intermediate transmuted material may be diffused to the solution. Givenby way of non-limiting examples, as discussed above the intermediatetransmuted material may include without limitation ²³⁹U and ²³⁹Np.

It will be appreciated that blocks of the methods 500 (FIGS. 5A-5D), 600(FIGS. 6A-6E), and 700 (FIGS. 7A-7G) may occur in any suitable hostenvironment. Given by way of non-limiting examples, the blocks may occurin any suitable reactor vessel, such as without limitation reactorvessels described above. In some embodiments, the blocks may occur insuitable nuclear fission fuel pins, such as without limitation nuclearfission fuel pins described above.

Referring now to FIG. 8A, in an embodiment an illustrative method 800 isprovided for fueling a nuclear fission reactor. The method 800 starts ata block 802. At a block 804 liquid carrier material is received in areactor core of a nuclear fission reactor. At a block 806 insolublefertile nuclear fission fuel material and soluble fissile nuclearfission fuel material are disposed in the liquid carrier material. Theliquid carrier material is neutronically translucent to the solublefissile nuclear fission fuel material, and the fertile nuclear fissionfuel material is transmutable into the fissile nuclear fission fuelmaterial. The method 800 stops at a block 808.

Referring additionally to FIG. 8B, in some embodiments the fissilenuclear fission fuel material may be dissolved in the neutronicallytranslucent liquid carrier material at a block 810.

Referring additionally to FIG. 8C, at a block 812 the fertile nuclearfission fuel material may be disposed in contact with a solution of thefissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material, the fertile nuclear fission fuelmaterial remaining undissolved in the solution.

Referring additionally to FIG. 8D, in some embodiments disposing thefertile nuclear fission fuel material in contact with a solution of thefissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material, the fertile nuclear fission fuelmaterial remaining undissolved in the solution, at the block 812 mayinclude disposing undissolved fertile nuclear fission fuel material indirect physical contact with the solution at a block 814. For exampleand referring additionally to FIG. 8E, in some embodiments disposing thefertile nuclear fission fuel material in direct physical contact with asolution of the fissile nuclear fission fuel material dissolved in theneutronically translucent liquid carrier material, the fertile nuclearfission fuel material remaining undissolved in the solution, at theblock 814 may include suspending fertile nuclear fission fuel materialin the solution at a block 816.

Referring additionally to FIG. 8F, in some embodiments disposing thefertile nuclear fission fuel material in contact with a solution of thefissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material, the fertile nuclear fission fuelmaterial remaining undissolved in the solution, at the block 812 mayinclude disposing, homogeneously in the reactor core, fertile nuclearfission fuel material in contact with a solution of the fissile nuclearfission fuel material dissolved in the neutronically translucent liquidcarrier material, the fertile nuclear fission fuel material remainingundissolved in the solution, at a block 818.

In some other embodiments and referring additionally to FIG. 8G,disposing the fertile nuclear fission fuel material in contact with asolution of the fissile nuclear fission fuel material dissolved in theneutronically translucent liquid carrier material, the fertile nuclearfission fuel material remaining undissolved in the solution, at theblock 812 may include disposing, heterogeneously in the reactor core,the fertile nuclear fission fuel material in contact with a solution ofthe fissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material, the fertile nuclear fission fuelmaterial remaining undissolved in the solution, at a block 820.

Given by way of non-limiting example and referring additionally to FIG.8H, in some embodiments disposing, heterogeneously in the reactor core,the fertile nuclear fission fuel material in contact with a solution ofthe fissile nuclear fission fuel material dissolved in the neutronicallytranslucent liquid carrier material, the fertile nuclear fission fuelmaterial remaining undissolved in the solution, at the block 820 mayinclude disposing undissolved fertile nuclear fission fuel material incontact with a solution of the fissile nuclear fission fuel materialdissolved in the neutronically translucent liquid carrier material in afertile blanket region of the reactor core at a block 822.

In another embodiment and referring now to FIG. 9A, an illustrativemethod 900 is provided for fabricating a nuclear fission fuel pin. Themethod 900 starts at a block 902. At a block 904 liquid carrier materialis received in an elongated enclosure of cladding. At a block 906insoluble fertile nuclear fission fuel material and soluble fissilenuclear fission fuel material are disposed in the liquid carriermaterial. The liquid carrier material is neutronically translucent tothe soluble fissile nuclear fission fuel material, and the fertilenuclear fission fuel material is transmutable into the fissile nuclearfission fuel material. The method 900 stops at a block 908.

Referring additionally to FIG. 9B, in some embodiments at a block 910the fissile nuclear fission fuel material may be dissolved in theneutronically translucent liquid carrier material.

Referring additionally to FIG. 9C, in some embodiments at a block 912the fertile nuclear fission fuel material may be disposed in contactwith a solution of the fissile nuclear fission fuel material dissolvedin the neutronically translucent liquid carrier material, the fertilenuclear fission fuel material remaining undissolved in the solution.

Referring additionally to FIG. 9D, in some embodiments the fertilenuclear fission fuel material may be disposed in contact with a wall ofthe elongated enclosure of cladding at a block 914.

Referring now to FIGS. 9A-9C and 9E, in some embodiments at a block 916an elongated enclosure of cladding may be defined, the elongatedenclosure having a first axial end, a second axial end, and acentralized axial region between the first and second axial ends.

Referring additionally to FIG. 9F, in some embodiments disposing in theelongated enclosure undissolved fertile nuclear fission fuel material incontact with the solution, the fertile nuclear fission fuel materialbeing transmutable into the fissile nuclear fission fuel material, atthe block 912 may includes disposing homogeneously in the elongatedenclosure undissolved fertile nuclear fission fuel material in contactwith the solution, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material, at a block918.

In some other embodiments and referring now to FIGS. 9A-9C, 9E, and 9G,disposing in the elongated enclosure undissolved fertile nuclear fissionfuel material in contact with the solution, the fertile nuclear fissionfuel material being transmutable into the fissile nuclear fission fuelmaterial, at the block 912 may include disposing heterogeneously in theelongated enclosure undissolved fertile nuclear fission fuel material incontact with the solution, the fertile nuclear fission fuel materialbeing transmutable into the fissile nuclear fission fuel material, at ablock 920.

For example and referring additionally to FIG. 9H, in some embodimentsdisposing heterogeneously in the elongated enclosure undissolved fertilenuclear fission fuel material in contact the solution, the fertilenuclear fission fuel material being transmutable into the fissilenuclear fission fuel material, at the block 920 may include, at a block922, disposing toward first and second axial ends of the elongatedenclosure undissolved fertile nuclear fission fuel material in contactwith the solution, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material.

Referring additionally to FIG. 9I, in some embodiments disposing in theelongated enclosure undissolved fertile nuclear fission fuel material incontact with the solution, the fertile nuclear fission fuel materialbeing transmutable into the fissile nuclear fission fuel material, atthe block 912 may include disposing in the elongated enclosureundissolved fertile nuclear fission fuel material in direct physicalcontact with the solution, the fertile nuclear fission fuel materialbeing transmutable into the fissile nuclear fission fuel material, at ablock 924. Given by way of non-limiting example and referringadditionally to FIG. 9J, in some embodiments disposing in the elongatedenclosure undissolved fertile nuclear fission fuel material in directphysical contact with the solution, the fertile nuclear fission fuelmaterial being transmutable into the fissile nuclear fission fuelmaterial, at the block 924 may include suspending fertile nuclearfission fuel material in the solution, the fertile nuclear fission fuelmaterial being transmutable into the fissile nuclear fission fuelmaterial, at a block 926.

Referring now to FIG. 10A, in another embodiment an illustrative method1000 is provided for fabricating a nuclear fission fuel pin. The method1000 starts at a block 1002. At a block 1004 liquid carrier materialthat is a solvent for fissile nuclear fission fuel material and that isneutronically translucent to the fissile nuclear fission fuel materialis disposed in an elongated enclosure of cladding. At a block 1006undissolved fertile nuclear fission fuel material is disposed in contactwith the neutronically translucent liquid carrier material, the fertilenuclear fission fuel material being transmutable into the fissilenuclear fission fuel material. The method 1000 stops at a block 1008.

Referring additionally to FIG. 10B, in some embodiments fissile nuclearfission fuel material may be dissolved in the neutronically translucentliquid carrier material at a block 1010.

Referring additionally to FIG. 10C, in some embodiments disposingundissolved fertile nuclear fission fuel material in contact with theneutronically translucent liquid carrier material, the fertile nuclearfission fuel material being transmutable into the fissile nuclearfission fuel material, at the block 1006 may include disposing,homogeneously in the elongated enclosure, undissolved fertile nuclearfission fuel material in contact with the neutronically translucentliquid carrier material, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material, at a block1012.

In some other embodiments and referring to FIGS. 10A, 10B and 10D,disposing undissolved fertile nuclear fission fuel material in contactwith the neutronically translucent liquid carrier material, the fertilenuclear fission fuel material being transmutable into the fissilenuclear fission fuel material, at the block 1006 may include disposing,heterogeneously in the elongated enclosure, undissolved fertile nuclearfission fuel material in contact with the neutronically translucentliquid carrier material, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material, at a block1014.

Given by way of non-limiting example and referring additionally to FIG.10E, in some embodiments disposing, heterogeneously in the elongatedenclosure, undissolved fertile nuclear fission fuel material in contactwith the neutronically translucent liquid carrier material, the fertilenuclear fission fuel material being transmutable into the fissilenuclear fission fuel material, at the block 1014 may include disposingtoward first and second axial ends of the elongated enclosureundissolved fertile nuclear fission fuel material in contact with theneutronically translucent liquid carrier material, the fertile nuclearfission fuel material being transmutable into the fissile nuclearfission fuel material, at a block 1016.

Referring additionally to FIG. 10F, in some embodiments at a block 1018an elongated enclosure of cladding may be defined, the elongatedenclosure having a first axial end, a second axial end, and acentralized axial region between the first and second axial ends.

Referring additionally to FIG. 10G, in some embodiments disposingundissolved fertile nuclear fission fuel material in contact with theneutronically translucent liquid carrier material, the fertile nuclearfission fuel material being transmutable into the fissile nuclearfission fuel material, at the block 1006 may include disposing in theelongated enclosure undissolved fertile nuclear fission fuel material indirect physical contact with the neutronically translucent liquidcarrier material, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material at a block1020. For example and referring additionally to FIG. 10H, in someembodiments disposing undissolved fertile nuclear fission fuel materialin direct physical contact with the neutronically translucent liquidcarrier material, the fertile nuclear fission fuel material beingtransmutable into the fissile nuclear fission fuel material, at theblock 1020 may includes suspending fertile nuclear fission fuel materialin the neutronically translucent liquid carrier material, the fertilenuclear fission fuel material being transmutable into the fissilenuclear fission fuel material, at a block 1022.

Referring now to FIGS. 10A and 10I, in some embodiments the fertilenuclear fission fuel material may be disposed in contact with a wall ofthe elongated enclosure of cladding at a block 1024.

Those skilled in the art will appreciate that the foregoing specificillustrative processes and/or devices and/or technologies arerepresentative of more general processes and/or devices and/ortechnologies taught elsewhere herein, such as in the claims filedherewith and/or elsewhere in the present application.

Those skilled in the art will recognize that it is common within the artto implement devices and/or processes and/or systems, and thereafter useengineering and/or other practices to integrate such implemented devicesand/or processes and/or systems into more comprehensive devices and/orprocesses and/or systems. That is, at least a portion of the devicesand/or processes and/or systems described herein can be integrated intoother devices and/or processes and/or systems via a reasonable amount ofexperimentation. Those having skill in the art will recognize thatexamples of such other devices and/or processes and/or systems mightinclude—as appropriate to context and application—all or part of devicesand/or processes and/or systems of (a) an air conveyance (e.g., anairplane, rocket, helicopter, etc.), (b) a ground conveyance (e.g., acar, truck, locomotive, tank, armored personnel carrier, etc.), (c) abuilding (e.g., a home, warehouse, office, etc.), (d) an appliance(e.g., a refrigerator, a washing machine, a dryer, etc.), (e) acommunications system (e.g., a networked system, a telephone system, aVoice over IP system, etc.), (f) a business entity (e.g., an InternetService Provider (ISP) entity such as Comcast Cable, Qwest, SouthwesternBell, etc.), or (g) a wired/wireless services entity (e.g., Sprint,Cingular, Nextel, etc.), etc.

In certain cases, use of a system or method may occur in a territoryeven if components are located outside the territory. For example, in adistributed computing context, use of a distributed computing system mayoccur in a territory even though parts of the system may be locatedoutside of the territory (e.g., relay, server, processor, signal-bearingmedium, transmitting computer, receiving computer, etc. located outsidethe territory).

A sale of a system or method may likewise occur in a territory even ifcomponents of the system or method are located and/or used outside theterritory.

Further, implementation of at least part of a system for performing amethod in one territory does not preclude use of the system in anotherterritory.

With respect to the use of substantially any plural and/or singularterms herein, those having skill in the art can translate from theplural to the singular and/or from the singular to the plural as isappropriate to the context and/or application. The varioussingular/plural permutations are not expressly set forth herein for sakeof clarity.

The herein described subject matter sometimes illustrates differentcomponents contained within, or connected with, different othercomponents. It is to be understood that such depicted architectures aremerely exemplary, and that in fact many other architectures may beimplemented which achieve the same functionality. In a conceptual sense,any arrangement of components to achieve the same functionality iseffectively “associated” such that the desired functionality isachieved. Hence, any two components herein combined to achieve aparticular functionality can be seen as “associated with” each othersuch that the desired functionality is achieved, irrespective ofarchitectures or intermedial components. Likewise, any two components soassociated can also be viewed as being “operably connected”, or“operably coupled,” to each other to achieve the desired functionality,and any two components capable of being so associated can also be viewedas being “operably couplable,” to each other to achieve the desiredfunctionality. Specific examples of operably couplable include but arenot limited to physically mateable and/or physically interactingcomponents, and/or wirelessly interactable, and/or wirelesslyinteracting components, and/or logically interacting, and/or logicallyinteractable components.

One skilled in the art will recognize that the herein describedcomponents (e.g., operations), devices, objects, and the discussionaccompanying them are used as examples for the sake of conceptualclarity and that various configuration modifications are contemplated.Consequently, as used herein, the specific exemplars set forth and theaccompanying discussion are intended to be representative of their moregeneral classes. In general, use of any specific exemplar is intended tobe representative of its class, and the non-inclusion of specificcomponents (e.g., operations), devices, and objects should not be takenlimiting.

While particular aspects of the present subject matter described hereinhave been shown and described, it will be apparent to those skilled inthe art that, based upon the teachings herein, changes and modificationsmay be made without departing from the subject matter described hereinand its broader aspects and, therefore, the appended claims are toencompass within their scope all such changes and modifications as arewithin the true spirit and scope of the subject matter described herein.It will be understood by those within the art that, in general, termsused herein, and especially in the appended claims (e.g., bodies of theappended claims) are generally intended as “open” terms (e.g., the term“including” should be interpreted as “including but not limited to,” theterm “having” should be interpreted as “having at least,” the term“includes” should be interpreted as “includes but is not limited to,”etc.). It will be further understood by those within the art that if aspecific number of an introduced claim recitation is intended, such anintent will be explicitly recited in the claim, and in the absence ofsuch recitation no such intent is present. For example, as an aid tounderstanding, the following appended claims may contain usage of theintroductory phrases “at least one” and “one or more” to introduce claimrecitations. However, the use of such phrases should not be construed toimply that the introduction of a claim recitation by the indefinitearticles “a” or “an” limits any particular claim containing suchintroduced claim recitation to claims containing only one suchrecitation, even when the same claim includes the introductory phrases“one or more” or “at least one” and indefinite articles such as “a” or“an” (e.g., “a” and/or “an” should typically be interpreted to mean “atleast one” or “one or more”); the same holds true for the use ofdefinite articles used to introduce claim recitations. In addition, evenif a specific number of an introduced claim recitation is explicitlyrecited, those skilled in the art will recognize that such recitationshould typically be interpreted to mean at least the recited number(e.g., the bare recitation of “two recitations,” without othermodifiers, typically means at least two recitations, or two or morerecitations). Furthermore, in those instances where a conventionanalogous to “at least one of A, B, and C, etc.” is used, in generalsuch a construction is intended in the sense one having skill in the artwould understand the convention (e.g., “a system having at least one ofA, B, and C” would include but not be limited to systems that have Aalone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). In those instances where aconvention analogous to “at least one of A, B, or C, etc.” is used, ingeneral such a construction is intended in the sense one having skill inthe art would understand the convention (e.g., “a system having at leastone of A, B, or C” would include but not be limited to systems that haveA alone, B alone, C alone, A and B together, A and C together, B and Ctogether, and/or A, B, and C together, etc.). It will be furtherunderstood by those within the art that typically a disjunctive wordand/or phrase presenting two or more alternative terms, whether in thedescription, claims, or drawings, should be understood to contemplatethe possibilities of including one of the terms, either of the terms, orboth terms unless context dictates otherwise. For example, the phrase “Aor B” will be typically understood to include the possibilities of “A”or “B” or “A and B.”

With respect to the appended claims, those skilled in the art willappreciate that recited operations therein may generally be performed inany order. Also, although various operational flows are presented in asequence(s), it should be understood that the various operations may beperformed in other orders than those which are illustrated, or may beperformed concurrently. Examples of such alternate orderings may includeoverlapping, interleaved, interrupted, reordered, incremental,preparatory, supplemental, simultaneous, reverse, or other variantorderings, unless context dictates otherwise. Furthermore, terms like“responsive to,” “related to,” or other past-tense adjectives aregenerally not intended to exclude such variants, unless context dictatesotherwise.

While various aspects and embodiments have been disclosed herein, otheraspects and embodiments will be apparent to those skilled in the art.The various aspects and embodiments disclosed herein are for purposes ofillustration and are not intended to be limiting, with the true scopeand spirit being indicated by the following claims.

What is claimed is:
 1. A nuclear fission reactor comprising: a reactorvessel; a fission region within the reactor vessel; a fertile blanketregion in the reactor vessel, the fertile blanket region being inhydraulic communication with the fission region and neutroniccommunication with the fission region; a solution, received in thefission region and the fertile blanket region, the solution including afirst fissile nuclear fission fuel material dissolved in neutronicallytranslucent liquid carrier material; and a solid, undissolved fertilenuclear fission fuel material in the fertile blanket region and indirect physical contact with the solution, the fertile nuclear fissionfuel material being transmutable into a second fissile nuclear fissionfuel material, the second fissile nuclear fission fuel material beingdiffusible directly into the solution within the reactor vessel.
 2. Thenuclear fission reactor of claim 1, wherein solubility of the secondfissile nuclear fission fuel material in the neutronically translucentliquid carrier material is greater than solubility of the fertilenuclear fission fuel material in the neutronically translucent liquidcarrier material.
 3. The nuclear fission reactor of claim 1, wherein thefertile nuclear fission fuel material is substantially insoluble in theneutronically translucent liquid carrier material.
 4. The nuclearfission reactor of claim 1, wherein the fertile nuclear fission fuelmaterial is provided in a form chosen from granular form, wire form,plate form, and foam form.
 5. The nuclear fission reactor of claim 1,wherein the solution and the fertile nuclear fission fuel material aredistributed homogeneously in the reactor vessel.
 6. The nuclear fissionreactor of claim 1, wherein the solution and the fertile nuclear fissionfuel material are distributed heterogeneously in the reactor vessel. 7.The nuclear fission reactor of claim 1, further comprising a pluralityof nuclear fission fuel pins received in the reactor vessel, each of theplurality of nuclear fission fuel pins having a first axial end and asecond axial end.
 8. The nuclear fission reactor of claim 7, wherein afirst portion of at least one nuclear fission fuel pin is disposed in afission region of the reactor vessel and at least a second portion ofthe at least one nuclear fission fuel pin is disposed in a fertileblanket region of the reactor vessel.
 9. The nuclear fission reactor ofclaim 7, wherein: the solution is distributed throughout each of theplurality of nuclear fission fuel pins; and the fertile nuclear fissionfuel material is received in first and second fertile blanket zonesdisposed toward the first and second axial ends, respectively, of eachof the plurality of nuclear fission fuel pins.
 10. The nuclear fissionreactor of claim 1, further comprising: a plurality of fertile blanketmodules disposed in the fertile blanket region, the fertile nuclearfission fuel material being received in the plurality of fertile blanketmodules.
 11. The nuclear fission reactor of claim 1, further comprising:at least one heat exchanger element in thermal communication with thesolution.
 12. The nuclear fission reactor of claim 11, wherein the atleast one heat exchanger element is immersed in the solution.
 13. Thenuclear fission reactor 11, further comprising: an annulus disposed inthe reactor vessel adjacent the at least one heat exchanger element suchthat natural circulation of the solution is establishable through the atleast one heat exchanger element and around the annulus.
 14. The nuclearfission reactor of claim 1, wherein a first concentration of the secondfissile nuclear fission fuel material in the fertile nuclear fissionfuel material is greater than a second concentration of the firstfissile nuclear fission fuel material in the neutronically translucentliquid carrier material.
 15. The nuclear fission reactor of claim 1,wherein the fission region is located toward a centralized region of thereactor vessel; and the fertile blanket region is located toward aperipheral region of the reactor vessel.
 16. The nuclear fission reactorof claim 15, wherein the reactor vessel is cylindrical.
 17. The nuclearfission reactor of claim 16, wherein the peripheral region of thereactor vessel includes a radially peripheral region.
 18. The nuclearfission reactor of claim 15, wherein the peripheral region of thereactor vessel includes an axially peripheral region.
 19. The nuclearfission reactor of claim 15, further comprising: a plurality of fertileblanket modules disposed in the fertile blanket region toward a radialperiphery of the reactor vessel, the fertile nuclear fission fuelmaterial being received in the plurality of fertile blanket modules. 20.The nuclear fission reactor of claim 1, wherein the fission region doesnot contain the undissolved fertile nuclear fission fuel material. 21.The nuclear fission reactor of claim 1, wherein diffusion of the secondfissile nuclear fission fuel material directly into the solution occursat the point of direct physical contact of the solution and the fertilenuclear fission fuel material and without the second fissile nuclearfission fuel material leaving the nuclear reactor.